We're racing towards the end of our A-Zdvent calendar of houses, so in the first of three final posts today here's a house in Inner Mongolia, China, by Multiplicities that's named after its X-shaped central void. Read more about (X) »

A painted-timber skin that skirts around the top storey reveals the heights of staggered floors inside this Hamburg house. Designed by Kraus Schoenberg, it's the W in our A-Zdvent calendar. Read more about Haus W »

The form of U-House by Jorge Graca Costa was inspired by traditional Mediterranean courtyard houses to protect it from the windy climate of western Portugal and it's the twenty-first door on our A-Zdvent calendar. Read more about U-House »

This conceptual house would be wrapped entirely in a plastic insulating material normally used on roofs. Intended for Łódź in Poland, it's the lowercase letter l in our A-Zdvent calendar. Read more about l House »